Ist ja übercool.Yes, cool is so established in German that academics use it in an email exchange on a technical topic. But I immediately thought that übercool here (meaning basically 'really cool') would be semantically different from English ubercool/übercool. (Seems that it's often written without the umlaut now in English.) I just assumed that English ubercool would have a negative ring to it — 'overly cool', 'tragically cool', or something. Well, lo and behold, it doesn't, based on googling around a little. There's a company called this, and Google describes its Google Financial interactive charts with this word, etc. One language borrowed an adjective from the other, which borrowed a prefix. Both end up with the same word meaning basically the same thing. That's just plain ubercool, in either language.
*Yes, I'm using singular they ('epicene they'). It was good enough for Chaucer, Shakespeare, the King James Bible, and Mark Twain, apparently.